Hypofractionated volumetric-modulated arc therapy for breast cancer: A propensity-score-weighted comparison of radiation-related toxicity

Int J Cancer. 2021 Jul 1;149(1):149-157. doi: 10.1002/ijc.33525. Epub 2021 Mar 8.


We assessed the clinical benefit of combining volumetric-modulated arc therapy (VMAT) and hypofractionated radiotherapy (HF-RT) considering the incidence of radiation-related toxicities. After a retrospective review for breast cancer patients treated with adjuvant RT between 2005 and 2017, a total of 4209 patients treated with three-dimensional conventional fractionation (CF-3D, 50.4 Gy/28 fractions) and 1540 patients treated with HF-RT (768 received HF-3D; 772, HF-VMAT; 40 Gy/15 fractions) were included. A total of 2229 patients (38.8%) received regional node irradiation (RNI): 1642 (39.0%), 167 (21.7%) and 420 (54.4%) received RNI via CF-3D, HF-3D and HF-VMAT, respectively. Acute/subacute and late toxicities were evaluated. Propensity scores were calculated via logistic regression. Grade 2+ acute/subacute toxicities was the highest in CF-3D group (15.0%, 2.6% and 1.6% in CF-3D, HF-3D and HF-VMAT, respectively; P < .001). HF-VMAT reduced Grade 2+ acute/subacute toxicities significantly compared to CF-3D (odds ratio [OR] 0.11, P < .001) and HF-3D (OR 0.45, P = .010). The 3-year cumulative rate of late toxicities was 18.0% (20.1%, 10.9% and 13.4% in CF-3D, HF-3D and HF-VMAT, respectively; P < .001). On sensitivity analysis, the benefit of HF-VMAT was high in the RNI group. Acute and late toxicities were fewer after HF-VMAT than after HF-3D or CF-3D, especially in women who underwent RNI.

Keywords: breast cancer; hypofractionated radiotherapy; radiotherapy dose fractionation; toxicity; volumetric-modulated arc therapy.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Breast Neoplasms / pathology
  • Breast Neoplasms / radiotherapy*
  • Dose Fractionation, Radiation
  • Female
  • Follow-Up Studies
  • Humans
  • Middle Aged
  • Prognosis
  • Propensity Score
  • Radiation Injuries / etiology
  • Radiation Injuries / pathology*
  • Radiotherapy, Intensity-Modulated / adverse effects*
  • Retrospective Studies